Cylinder Head Oil Gallery Plugs, Turbocharger Studs, Spark Plugs, and Engine Oil Manifold Check Valve Removal

Procedure

1. Inspect the oil feed check valves. Damaged, restricted or clogged check valves must be replaced. If check valves are OK, disregard remaining steps which detail replacing the check valves.
2. Insert a punch or drift into the check valve. With moderate pressure, seat the punch into the inner body of the check valve, and remove the upper part of the valve.
3. Remove check ball and check ball spring from inside of check valve.
4. Using EN-46122-3  drill bit, drill the remainder of check valve sleeve to a depth of approximately 19 mm (0.75 in) by placing tape on drill bit as a depth gauge. It is not necessary or desirable to drill completely through the bottom of the check valve.
5. Lubricate EN-46122-4  tap with lubricant. Tap drilled out portion of check valve remaining in cylinder head. Tap to full depth possible until tap bottoms out in head.
6. Assemble EN-46122-2  bolt, nut, washers, and collar. Position collar with slightly-larger inside diameter DOWN toward the cylinder head.
7. Screw bolt by hand fully down into threaded check valve sleeve, then lightly tighten nut against washer.
8. Hold bolt with one wrench, and use another to tighten the nut until the check valve sleeve is removed from the cylinder head.
9. Clean check valve bore and related passages thoroughly to remove any drilling chips or other debris.